Future directions in genome-wide association studies of schizophrenia spectrum disorders

The rapid expansion of diagnostic technologies in general and of the genome-wide association studies method in particular brings us closer to the understanding of the etiopathogenetic fundamentals of endogenous mental disorders. The amount of accumulated experience in genome-wide association studies allows one to assess the importance of specific genetic markers in the development of the diseases of interest. The introduction of screening systems and the assessment of disease prognosis is yet to be implemented, due to conceptual and methodological contradictions. The present review aims at analyzing the current progress in the field of genetic studies of schizophrenia spectrum disorders. The prospects and limitations of existing methods and the obstacles to the efficient translational application of the achievements of GWAS and candidate gene studies are discussed. Along with the still poor understanding of the etiology and pathogenesis of schizophrenia spectrum disorders, such issues as the ongoing debate regarding the correct classification, as well as the large degree of symptom heterogeneity within this group of conditions, remain a cornerstone in biologicalresearch. A more accurate approach to phenotyping, including the application of deep phenotyping techniques, is required to form more homogenous samples for future genome-wide association and candidate gene studies of schizophrenia spectrum disorders.